It's not simple to buy light bulbs these days. What's with all these choices? The latest energy bill passed by the US Congress has banned incandescent bulbs, effective by year 2014. That means that over the next four years we will all be replacing the light bulbs we've used since Thomas Edison's invention in the 1800s.

Two options are standing out as the future of light bulbs - the proven Compact Fluorescent (CFL) bulbs and the newcomer, Light Emitting Diode (LED) light bulbs.

Below are the results of our lumination tests and a summary of the lifetime costs of each type of bulb. There are two tests, one each for the accent and floodlight bulbs.

Accent Bulb Test:

Technology

Incandescent

CFL

LED

Bulb

GE Reveal 75 watt

GE Energy Smart Soft White 60 watt replacement (15 watt actual)

Sylvania 2 Watt Accent LED S14 Bulb (10-15 watt replacement)

Price / bulb

$1.00

$4.00

$14.00

Expected Life

750 hours

8,000 hours

30,000 hours

10 year electricity cost

$247.50

$49.50

$24.75

10 year total cost

$287.50 (40 bulbs)

$65.50 (4 bulbs)

$38.75 (1 Bulb)

Note: Expected total 10 year cost includes cost of bulbs and electricity, with electricity calculated at $.11 per KwH

The images clearly show that the CFL is close in performance to the incandescent. Both would work for most lamp lighting applications. The LED bulbs were a different story. At this point, there are no LED bulbs that truly compete with the 60 watt incandescent. There are many claims but none reach the lumen output necessary. The US Department of Energy is currently taking submissions for a competition called the L-Prize, awarding $10 million to the company that achieves a 60 watt equivalent bulb for the mass marketplace, but to date, there is only one entry.

The CFLs and LEDs are cheaper than incandescents in the long run, but the upfront cost and availability of the CFLs make them the better choice for accent and general purpose applications.

Floodlight Bulb Test:

Technology

Incandescent

CFL

LED

Bulb

GE Soft White Floodlight 45 watt

Philips Energy Saver 50 Reflector Flood (14 watt actual)

GE Energy Smart PAR30 Long Neck LED Floodlight (10 watt actual)

Price / bulb

$3.00

$10.00

$41.00

Expected Life

2,000 hours

8,000 hours

20,000 hours

7 year electricity cost

$88.00

$31.00

$22.00

7 year total cost

$118.00 (10 bulbs)

$61.00 (3 bulbs)

$63.00 (1 Bulb)

As the images show, the CFL and LED flood lights are comparable to the incandescent in this front hallway application. For most applications that don't require substantial amounts of light, any of the bulbs would suffice. If more light is required for your particular tasks, then you may want to go up in wattage or wattage equivalence.

On the pricing front, both CFL and LED outperformed the incandescent flood light, offering a savings in the range of half the cost over a 7 year period.

Conclusions:

Incandescents are on the way out. Over the next four years we expect the technology in CFLs and LEDs to both outperform incandescents to an even greater degree and to reach price points that are workable for most households. In the long run, CFLs and LEDs will not only save the consumer large sums of money but also use measurably less electricity.

We would be remiss if we didn't talk about mercury, the issue that makes CFL bulbs unappealing to many consumers. There is mercury vapor in every fluorescent bulb on the market. The amount of mercury is coming down, and with proper handling and disposal, this toxin poses little danger to the consumer. The amount of mercury in each CFL bulb today is actually less than the amount of mercury emitted by a coal burning power plant as it powers the difference between a CFL and incandescent bulb. So in fact using CFLs offers a net reduction in mercury emissions into the atmosphere if your electricity is supplied by a coal-fired plant.

Nonetheless, the mercury issue is still what will eventually push LEDs to the top of the market. With longer life, increasing performance and no mercury, LED bulbs will likely become the standard within the next decade. Prices have already reached a point where over the life of the bulb, they cost the same as name brand CFL bulbs.

You may not be able to afford the LED replacement investment today, but over time, we will all be using LEDs to light our world.